How to determine if a file is in use

[Richard England]

On 11/03/2009 01:31 PM, Donald Russell wrote:
> Another system uses FTP to drop files in a directory for me to process.
> I have a bash script to process the incoming files. The script is 
> started by cron periodically.
>
> There's a problem if the FTP transfer is still in progress because the 
> process begins reading the file even though it isn't complete yet.
>
> From a bash script, is there a way to tell if the file is still being 
> written to?
> I was looking at the lsof command, which will tell me if the file is 
> opened or not, so that's a possibility... but it sure seems awkward 
> for the task.
>
> I could also configure the ftp server to lock files being written, but 
> that seems to be discouraged. (based on man vsftpd.conf)
>
> Basically, what I want is something like
> Can I get an exclusive read on file x?
> No - skip that file, go onto the next one
> Yes - start processing that file
> (I'm not concerned about the possible race condition there... I have 
> other protections for that)
>
> Thanks for any suggestions...
>
>
>

Perhaps "fuser" might be of use?

-- 
------------------------------------------------------------------------
/~~R/